What are waterproof clothing standards?

 

You need the right waterproof corporate clothing and workwear to stand up to your extreme environment, so in this article we are going to cover the EN 343 standard and the factors you can check to make sure your outdoor protective clothing is right for you and your working conditions, and you’re left dry at the end of every shift.

 

 

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MF Recommendation and summary:

To sum this article up, waterproofness of workwear is measured in two tests.

EN 343 is a basic rating 0-4, which gives an indication of how waterproof a garment will be.

However, it can’t be used to compare garments because it isn’t a specific measurement, and in our experience a coat with a rating of 4 may still get the wearer wet during a sustained downpour, in part combined with other factors like whether the seams are sealed or not.

Therefore, look for a rating measured in mm, as this is a direct representation of how waterproof a garment is.

While a manufacturer can call a garment waterproof at 1,500mm, in reality this is only showerproof, and we recommend looking for at least 10,000mm waterproof rating on anything which is going be worn outside in the rain for more than a few minutes.

Some of the best jackets are like the AK9-A20 Leo Marisco hi-vis jacket, and the AK9-T400 for the Portwest T400 hi-vis jacket which measure 20,000mm and 15,000mm respectively.

As always, quality does come with a cost though, so this needs to be considered. At the end of the day, good waterproofs aren’t cheap.

Give us a call for more information, and to see what jacket we’d recommend for your environment!

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EN 343:

EN 343:2019 is a European standard for classifying the properties of protective clothing and workwear. The standard tests the garment’s breathability and ability to withstand heavy water pressure (including precipitation, fog and humidity).

This is what you’ll see on the label:

The standard has three values which indicate the level of protection.

• The first value indicates the product’s waterproofness
• The second value refers to the breathability of the product

Both are measured on a scale of 1-4, with 4 being the highest value which gives the most protection.

• The third value is indicated by either an ‘R’ or an ‘X’. The R means the product has been tested in a downpour, which is an optional test.

The EN 343 standard for workwear also involves pre-treatment and durability testing, which includes flexing, tear resistance, abrasion and washing. This means it is tested before and after simulation of real life conditions rather than just as a new garment.

 

Breathability:

How breathable a garment is refers to how well it allows inside moisture to evaoprate i.e. sweat and vapour. This has the benefit of keeping the wearer cooler and dryer.

If you ever see a RET measurement on a garment, which is likely to be in addition to the EN 343 breathability value as shown above, this is a measure of how well a fabric allows evaporation. The thermal evaporative resistance (RET) coefficient measures the capacity of a fabric to stop water vapour getting out. The lower this resistance (i.e. the lower the value), the more breathable the fabric is. The test method is defined by the ISO 11092 standard.

It may seem obvious, but one thing to remember is that if you need a waterproof jacket with a high breathability rating it is very unlikely that you will find one with a padded or quilted lining. This is because a jacket that traps body heat in – designed for cold weather – is also likely to trap moisture in too.

Railway workers often must have jackets specified with a high breathability rating as well as conforming to RIS TOM orange hi-vis.

 

Waterproof vs water repellent vs water resistant:

When you’re looking for waterproof clothing you’re also likely to come across the terms water repellent and water resistance. Don’t be fooled into thinking they all mean the same though – they don’t!

Water resistant – this typically offers the lowest level of water protection, and the resistance usually comes from the weave of the fabric itself acting as a barrier in case there is a light rain shower, as it would take some time for water to seep through the material.

Water repellent – this is better than water resistant as it means that water beads on the outside of the material (hydrophobic effect). Often, this will be achieved by coating the fabric with a wax or spray or other durable water repellency coating, and it will often need re-coating as it is less durable than other waterproof jackets.

Waterproof – if you’re caught outside in a torrent of rain you’d better hope your jacket is waterproof! This means the fabric is able to resist the pressure of the water, and it’s a key difference from resistance and repellent. While it does vary – as explained below – a higher millimeter rating means a jacket can withstand more water at a higher pressure than merely being ‘shower resistant’.

 

Waterproof ratings:

Now, you know what the EN 343 standard is and how it applies to workwear and covers breathability, durability and waterproof-ness, but if you want more precise information about how much water your jacket will protect you from before you start to get wet, then you need to be looking out for a figure stated in millimeters. This refers to the results of the hydrostatic head test, or water column.

Typically this is found on the higher quality jackets, and this also applies to the fashion/outdoor market as well – not just corporate clothing.

Before we explain what the ratings mean, let’s have a look at how the test is conducted:

In a Hydrostatic Head test, the fabric is pulled tight under a 1 inch diameter sealed tube of water. This is then observed over 24 hours to ascertain how many millimetres of water the fabric can withstand before it soaks through. The level at which water starts to come through the fabric is the hydrostatic head, which is measured in mm.

Traditionally the test is carried out using a physical column of water but as fabrics have developed the ratings were getting too high for this method. Having the facilities to hold a 30 metre high water column is a bit unrealistic even for scientific test centres, therefore the test is done using a machine that replicates the downward pressure that a water column of such height would create.

The machine increases the pressure of water that is pushed against the fabric until water is visible on the other side. The required level of pressure used to force water through the fabric is then converted into a measurement of how high the water column would have been. This provides the result of the Hydrostatic Head test in millimetres.

In the UK manufacturers are allowed to claim a fabric is waterproof if the Hydrostatic Head is 1500mm but most waterproof jackets exceed this comfortably and figures of 10,000 to 30,000mm are not uncommon. Fabric for use in garments require higher levels of waterproofing because garments are subjected not only to driving rain but also to pressure applied by straps and belts of rucksacks. Anything under 1500mm is generally only considered water resistant.

Hydrostatic ratings:

Rating	Resistance	Weather
0 – 1,500mm	Water resistant	Very light rain
1,500mm – 5,000mm	Waterproof	Light to average rain
5,000mm	Very Waterproof	Moderate to heavy rain
10,000mm – 20,000mm and above	Highly Waterproof	Heavy rain

 

Each garment will vary as products are designed for different needs, and it is always better to check the manufacturers data sheet to be certain what protection your waterproof workwear gives.

For example, the Leo Marisco jacket gives one of the highest ratings of 20,000mm which is suitable for workers needing hi-vis in the most extreme exposed conditions and sustained rain. The recycled Orn Fireback EarthPro jacket gives a 10,000mm rating which is again perfect for looking smarter in black and navy whilst still needing extreme protection.

 

Can taped seams & design help?

Short answer: Yes.

If you’ve ever been asked by workers why their cheap hi-vis stormcoats let in rain after being out for a period of time, this may be why:

Even if a garment is treated with a waterproof coating and has a waterproof membrane it may still not be fully waterproof. The quality of the seams and to an extent the jacket’s design will also affect whether you are going to get wet. For a jacket to be 100% waterproof it will also need to have taped seams. These are heat sealed seams that stop water coming through the stitching. To some extent this is the norm on higher quality jackets but it is always worth checking. Hood and garment design also matters, as this can affect how much water gets in on a long wet day working outside.

 

Next steps:

Now you know what to look out for when buying waterproof clothing and workwear, get in touch with us with your need and we’ll help source a solution for you, or browse our outdoor jackets and wet weather gear online!